Copying machine having top wall with slit for cleaning access

ABSTRACT

A copying machine has a top wall with a slit which remains covered during a copying operation by a board for carrying an original to be copied. When the machine is not in use, the board can be moved so as to expose the slit. The slit is elongated transversely to the direction of motion of the board and a passage is provided under the top wall and through a reflector member such that a tubular cleaner member can be not only inserted through the slit to reach an internal component such as the charger wire which requires cleaning but also moved transversely along the slit. Thus, the internal component can be cleaned without removing the top wall.

This application is a continuation of application Ser. No. 07/356,003,filed May 23, 1989, now abandoned.

FIELD OF THE INVENTION

The present invention relates to a copying machine having an arrangementfor the easy cleaning of, for example, a charging wire for a maincharger from the outside of the machine.

BACKGROUND OF THE INVENTION

In an electrostatic copying machine, it is required that prior to thestage of exposing the surface of a photoreceptor to light, the surfaceof the photoreceptor be subjected to electrostatic charging. For thispurpose, a main charger is placed near the photoreceptor. This maincharger has a charge wire placed adjacent a photoconductive layer of thephotoreceptor and made of a fine tungsten wire. As a high voltage isapplied to the charge wire, corona from the charge wire makes airborneparticles ionize and the ionized particles deposit on the surface of thephotoreceptor to charge the surface thereof.

The aforementioned charge wire is liable to gather dust while thecopying machine is in use, and the dust on the charge wire causes blursor lines on a copied image. Therefore, it is necessary that the chargewire must be subjected to periodic cleaning.

The charge wire of the main charger is usually cleaned by opening afront casing member, taking out the main charger incorporated in themachine, and wiping the charge wire placed in the main charger.

However, any arrangement for opening the front casing member and takingout the main charger so as to clean the charge wire of the main chargeris disadvantageous in that the construction of the copying machine ismade complex and the copying machine is necessarily larger in size andheavier. This results in an increase in the manufacturing cost.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a copying machinearrangement which enables easy cleaning of its components, such as acharge wire of a main charger, from outside the machine without openinga front casing member and taking out the main charger from the machine.

It is another object of the invention to provide an arrangement whichprevents dust and the like from entering the copying machine through aslit in the casing member during copying operation or the like. When itis required to clean components of the machine, a cleaner is insertedinto the machine from outside through an open gap of a passage forcleaner insertion so that the components of the machine can be cleanedonly by externally controlling the cleaner.

It is another object of the invention to provide an arrangement whichenables direct cleaning of components of the copying machine to therebyconsiderably reduce the number of components of the machine. This makesthe machine compact, lightweight, and less expensive.

It is a further object of the invention to provide an arrangement whichpermits smooth cleaning operation with respect to interior components atmuch higher efficiency.

It is a still further object of the invention to provide an arrangementwhich makes it possible to considerably improve the operationalefficiency and cleaning efficiency and which prevents light from anexposure lamp from leaking through the passage for cleaner insertion andalso prevents the entry of stray light or the like from an externallight source or the exposure lamp onto the photoreceptor drum in themachine. This permits good copying performance to be maintained.

It is another object of the invention to provide increased flexibilityof design for a copying machine and minimize the clearance between areflector and a main charger in order to contribute to the furtheranceof size reduction, weight reduction, and cost reduction in themanufacture of copying machines.

It is another object of the invention to provide an arrangement whichpermits smooth cleaner operation for interior components withoutinvolving plastic deformation of a flexible sheet for shutting off thecleaner insertion passage.

In order to accomplish the foregoing objects, the present inventionprovides a copying machine comprising a casing member forming a top wallof the machine, this casing member having a slit for directing the lightfrom an exposure lamp which is disposed under this casing member, towardan original setting board, and the original setting board being movableon the casing member for reciprocation in the right and left directions,characterized in that the movable range of the original setting board isdefined so that the slit is covered by the original setting boardirrespective of the position of the original setting board during itsreciprocating movement on the casing member for copying operation, andin that the original setting board is movable beyond the movable rangeat least in one direction, either rightward or leftward, when it is notin copying operation, the limit for said movement in one direction ofthe original setting board being set so that an open gap is definedbetween an edge of the original setting board and an edge of the slit toprovide a passage for cleaner insertion which leads to the interior ofthe machine, when the original setting board is moved beyond the movablerange. Also, the edge of the original setting board and the edge of theslit are so formed as to serve as a guide for the cleaner duringcleaning operation.

The foregoing arrangement eliminates the necessity of adapting the frontcasing member of the copying machine to be opened and closed and/ordesigning the main charger and the like to be detachable from themachine, for the purpose of cleaning the charge wire for the maincharger incorporated in the machine. Therefore, the number of componentsof the copying machine can be considerably decreased, this being thuspossible to further size reduction weight reduction, and cost reductionof copying machines. Further, according to the invention, interiormembers to be cleaned can be readily cleaned only by inserting a cleanerinto the cleaner insertion passage through the open gap defined betweenthe edge of the original setting board and the edge of the slit andoperating the cleaner from the outside of the machine; thus, cleanercontrol and cleaning efficiency can be considerably improved.

In another copying machine of the invention, there is provided, on thecleaner insertion passage accessible from outside a machine, a flexiblesheet having light shielding properties in such a way as to shut off thepassage. The flexible sheet may consist of one sheet only, butpreferably it consists of at least two sheets. When the flexible sheethaving light shielding properties includes a plurality of sheets, theyare individually disposed at an outer side and at an inner side of themachine, on the cleaner insertion passage accessible from outside themachine, in spaced apart and opposed relation, in such a way as to shutoff the passage.

In still another copying machine in accordance with the invention,flexible sheets having light shielding properties are individuallydisposed at the outer side and at the inner side on the cleanerinsertion passage accessible from outside the machine, in spaced apartand opposed relation, in such a way as to shut off the passage, and theflexible sheet disposed at the outer side has light reflectingproperties so that it concurrently serves as a part of a reflector. Theflexible sheet disposed at the inner side has electroconductiveproperties so that it concurrently serves as a part of a main chargercase.

In still another copying machine according to the invention, flexiblesheets having light shielding properties are individually disposed at anouter side and at an inner side on a cleaner insertion passageaccessible from outside the machine, in spaced apart and opposedrelation, in such a way as to shut off the passage, and the flexiblesheet disposed at the outer side is formed with an inclined edge portionalong a flexible sheet portion where the cleaner is inserted so as toenable a longitudinally extending edge portion of the sheet to upstandin the outward direction as the inserted cleaner moves in a lateraldirection, while on the other hand the flexible sheet disposed at theinner side has a longitudinally extending edge portion of the sheetadapted to downstand in the inward direction as the inserted cleanermoves in the lateral direction.

Through above described arrangement, it is possible to achieve sizereduction, weight reduction, and low cost production of copyingmachines. The arrangement makes it possible to clean interior componentsonly by inserting a cleaner into the cleaner insertion passage fromoutside and externally controlling the cleaner, and therefore improvedcleaner control and improved cleaning efficiency can be obtained. At thesame time, stray light from the outside onto the photoreceptor drum inthe machine can be prevented. Thus, good copying performancecharacteristics can be maintained. Furthermore, the clearance betweenthe reflector and the main charger can be minimized and, in addition,the arrangement permits smooth cleaning operation with respect to theinterior components without plastic deformation of the flexible sheets.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 through 9 show an embodiment of the invention.

FIG. 1 is a fragmentary schematic block diagram showing principal partsof the internal construction of a copying machine;

FIG. 2 is a schematic block diagram showing a condition of the copyingmachine when a charge wire for a main charger is being cleaned by acleaner having its charger-cleaning front end portion inserted fromoutside into the interior of the machine;

FIGS. 3 through 5 are, respectively, explanatory views showing themovable range of an original setting board during copying operation;

FIG. 6 is an explanatory illustration showing the position of theoriginal setting board which is set as the limit for its movement wheninterior components for cleaning are to be cleaned by external cleaningcontrol while the board is not in copying operation;

FIG. 7 is a perspective view showing principal parts of a flexible sheetmounted on a reflector;

FIG. 8 is a fragmentary perspective view showing a condition of twoflexible sheets mounted on the reflector when they are temporarilyopened by a cleaner inserted;

FIG. 9 is a perspective view of a cleaner.

FIGS. 10 and 11 illustrate another embodiment of the invention.

FIG. 10 is a fragmentary schematic block diagram showing principal partsof the internal construction of the copying machine; and

FIG. 11 is a fragmentary schematic block diagram showing the conditionof the copying machine when a charge wire for a main charger is beingcleaned by a cleaner having its front end portion inserted from outsideinto the interior of the machine.

DESCRIPTION OF THE EMBODIMENTS

One embodiment of the invention is described below with reference toFIGS. 1 through 9.

As shown in FIGS. 1 and 2, a casing member 1 which constitutes a topwall of a copying machine is formed with an elongate slit 2 having apredetermined width extending in a direction perpendicular to thedirection of the movement of an original setting board 4 which is ableto laterally move reciprocatingly on the casing member 1. Under thecasing member 1 there is disposed an exposure lamp 3 so that lightprojected from the exposure lamp 3 is directed through the slit 2 towardthe transparent original setting board 4 which is slidable on the casingmember 1.

The aforementioned original setting board 4 on which an original is tobe placed automatically and reciprocatingly moves laterally on thecasing member 1 during a copying operation, and the aforementioned slit2 is always covered by the original setting board 4 in this stateirrespective of the position of the original setting board 4 during itsmovement for a copying operation. In other words, as shown in FIGS. 3through 5, a moving range E of the original setting board 4 is definedso that the slit 2 in the casing member 1 is covered by the originalsetting board 4, even when the original setting board 4 is positioned ata right end or a left end of its moving range E during a copyingoperation.

The foregoing relationship between the slit 2 in the casing member 1 andthe original setting board 4 during a copying operation will beexplained in further detail. In the condition shown in FIG. 3, thecenter line of the original setting board 4 coincides with that of thecasing member 1. It is needless to say that the slit 2 is covered by theoriginal setting board 4 in this state.

In the condition shown in FIG. 4 in which the original setting board 4has been moved to the left end of the range E in accordance with theprogress of the copying operation, the right edge 4a of the originalsetting board 4 is positioned close to the slit 2, but the slit 2 isstill covered by the right edge peripheral portion of the originalsetting board 4.

Similarly, with a further progress of the copying operation, when theoriginal setting board 4 has moved to the right end of its moving rangeE, as shown in FIG. 5, a left edge 4b of the original setting board 4 ispositioned close to the slit 2, and the slit 2 is still covered by theleft edge peripheral portion of the original setting board 4.

In this way, whatever position within the moving range E the originalsetting board 4 may be situated at, the slit 2 in the casing member 1 iscovered by the original setting board 4. Therefore, external dust, etc.can be effectively prevented from entering into the machine through theslit 2.

When the copying machine is not being operated, as shown in FIG. 6, theoriginal setting board 4 moves a little further in at least onedirection to the right or left, beyond the moving range E. In thepresent embodiment, the original setting board 4 can be moved to theright to a limit F beyond the moving range E. When the original settingboard 4 is moved to the limit F as shown in FIGS. 1, 2 and 6, the widthof the slit 2 and the movement limit F of the original setting board 4are set under relative conditions so that an open gap 5a for a cleanerinsertion passage 5 leading to the interior of the machine is definedbetween the left edge 4b of the original setting board 4 and a left edge2a of the slit 2.

The left edge 4b of the original setting board 4 and the left edge 2a ofthe slit 2 are so formed as to serve as a guide so that they can guide acleaner A when the cleaner A is inserted through the open gap 5a of thecleaner insertion passage 5 and is laterally moved.

With reference to FIG. 1, there is disposed, close to the lower part theexposure lamp 3, a reflector 6 for reflecting light projected from theexposure lamp 3 and directing the light through the slit 2 toward theoriginal setting board 4. This reflector 6 is made of sheet metal, forexample. The reflector 6, in its portion positioned on theaforementioned cleaner insertion passage 5, is provided with an opening6a through which the cleaner A can be inserted. The opening 6a extendsin the longitudinal direction of the reflector 6 as shown in FIG. 7.

Two flexible sheets 7, 8 having light shielding and light reflectingproperties are placed on the reflector 6, at the upper and lower sidesthereof respectively, with the aid of an adhesive agent or an adhesivedouble coated tape in such a way that the flexible sheets 7 and 8 areopposite to each other with a predetermined spacing in between so as tocover the opening 6a. The outer flexible sheet 7, or both flexiblesheets 7, 8 have light reflecting properties. To explain morespecifically, aluminum is deposited over the surface of the flexiblesheet to provide light reflecting properties. The cleaner insertionpassage 5 is shut off at its mid-point by the two flexible sheets 7, 8so that the cleaner insertion passage 5 is shielded from light. Sincethe flexible sheets 7, 8 are provided with light reflecting properties,they can serve as a part of the reflector 6.

The outside flexible sheet 7 located on the cleaner insertion passage 5is placed with adhesive on the upper side of the reflector 6 as shown inFIGS. 7 and 8. A bonded area X of the flexible sheet 7 on the reflector6 covers the entire area of the lower end portion of the flexible sheet7 extending along the wall portion of the reflector 6 under the opening6a thereof and, as required, the side edge portions and a part of theupper edge portions adjacent thereto of the flexible sheet 7, asindicated by oblique lines in FIG. 7. The upper end portion of theflexible sheet 7 excepting the bonded area X is a non-bonded area Y. Alongitudinal edge portion 7a of the sheet which corresponds to thenon-bonded area Y is normally in close contact with the reflector 6, butas shown in FIG. 8, the longitudinal edge portion 7a of the sheet isseparated from the reflector 6 and partially raised when the cleaner Ais inserted through the opening 6a.

Further, the flexible sheet 7 has an inclined edge 7b formed by cuttinga part of the sheet from its upper edge along the cleaner insertionpassage 5. The edge 7b is upwardly inclined in the direction ofpost-insertion movement of the cleaner A (the direction of arrow C). Theflexible sheet 7 also has a tongue 7c formed on the cleaner insertionpassage 5. The tongue 7c has an inclined edge parallel to the inclinededge 7b and extends downwardly from the upper end of the flexible sheet7. The cleaner insertion passage 5 is partially shut off by the tongue7c. In the case that a flexible sheet 8 is disposed opposite to theflexible sheet with a predetermined spacing in between, the tongue 7c isnot needed. Thus, when the front end portion of the cleaner A isinserted, pushing the tongue 7c positioned on the cleaner insertionpassage 5 and then this cleaner A is laterally moved as shown in FIG. 8,the inclined edge 7b of the flexible sheet 7 is raised by the cleaner A.Accordingly the longitudinal sheet edge 7a which constitutes thenon-bonded area Y of the flexible sheet 7 is caused to be partiallyraised toward the outer side. This permits the lateral movement of thecleaner A.

Meanwhile the inner side flexible sheet 8 disposed opposite to theflexible sheet 7 with a predetermined spacing in between is bonded tothe underside of the reflector 6. In contrast with the flexible sheet 7,this flexible sheet 8 is bonded to the upper wall portion of thereflector 6 extending along the opening 6a thereof and a longitudinalsheet edge 8a of the flexible sheet 8 which is positioned at the lowerwall side of the opening 6a is normally in close contact with thereflector 6, as shown in FIGS. 7 and 8. The longitudinal sheet edge 8aconstitutes a non-bonded area which is separated from the reflector 6 soas to partially hang down, being deflected when a force from the cleanerA is applied. Therefore, when the front end portion of the cleaner A ispushed in and moved laterally, the longitudinal sheet edge 8a of theflexible sheet 8 is caused to partially hang down toward the inner side.

At a location a little away from the flexible sheets 7, 8 in thereflector 6, there is formed a slit 6b as shown in FIG. 1. The slit 6bguides the light reflected from the original on the original settingboard 4 to a Selfoc lens 9 disposed under the reflector 6, after theoriginal is exposed to light from the exposure lamp 3.

As also shown in FIG. 1, a main charger 10 is disposed under theflexible sheets 7, 8 on the cleaner insertion passage 5, and a chargewire 10b is placed in a main charger case 10a of the main charger 10.The main charger case 10a is provided formed with an opening 10c whichpermits the insertion and lateral movement of the cleaner A.

A photoreceptor drum 11 is rotatably disposed in the interior of thecopying machine. The main charger 10 and the Selfoc lens 9 aresequentially disposed around the photoreceptor drum 11. Further, aroundthe photoreceptor drum 11 there are disposed a developing unit 12, acopying sheet guide 13, a transfer charger 14, a separation roller 15,and a cleaning unit 16, in this order.

Secondly, the operation of the copying machine will be explained. When acopy switch is turned ON after an original is placed on the originalsetting board 4 and an original cover (not shown) is placed on theoriginal, high voltage is applied to the charge wire 10b of the maincharger 10, whereupon corona develops from the charge wire 10b to ionizeairborn particles. The resulting ions deposit on the surface of thephotoreceptor drum 11, and thus the outer periphery of the photoreceptordrum 11 is charged.

Meanwhile, the original setting board 4 goes into reciprocating movementin the right and left directions within the moving range E on the casingmember 1, whereupon a part of the light projected from the exposure lamp3 is reflected by the reflector 6 and the outer flexible sheet 7 whichconstitutes a part of the reflector 6, and the substantially entirequantity of the light is directed to the original on the originalsetting board 4 through the slit 2 of the casing member 1. The lightreflected from the original slit 6b of the reflector reaches the Selfoclens 9 via the 6, and the charged surface of the photoreceptor drum 11is exposed to light through the Selfoc lens 9 to form a latent image.

A latent image formed on the photoreceptor drum 11 is developed by thedeveloping unit 12 into a visible toner image, which is thereaftertransferred as a visible image by the transfer charger 14 onto a copyingsheet delivered by means of the copying sheet guide 13. Then, thecopying sheet is separated by the separation roller 15 from thephotoreceptor drum 11 and subsequently the visible image on the copyingsheet is fixed by a fixation unit (not shown). Thereafter, the copiedsheet is transferred out of the machine. Any residual toner present onthe photoreceptor drum 11 is removed by the cleaning unit 16 and thestatic of the photoreceptor drum 11 is eliminated. Thereafter, thephotoreceptor drum 11 again goes into the charge zone where thephotoreceptor drum 11 is charged by the main charger 10.

When this copying operation is repeated, dust is likely to deposit onthe charge wire 10b of the main charger 10 and the accumulated dustcauses blurs and/or lines on the copied image left as they are.Therefore, it is required that the charge wire 10b is subjected toperiodical cleaning.

For this purpose, the original setting board 4 is moved to the limit Fset in one direction (in the direction of arrow B in the presentembodiment) beyond the moving range E, whereby an open gap 5a is definedbetween the left edge 4b of the original settling board 4 and the leftedge of 2a of the slit 2, as shown in FIGS. 1 and 6. A charger cleaningfront end portion A' of the cleaner A is inserted through the open gap5a of the cleaner insertion passage 5 leading inside the machine, asshown in FIG. 2.

It is noted in this connection that the position at which the chargercleaning front end portion A' of the cleaner A is inserted ispredetermined. As the cleaner A is inserted into the cleaner insertionpassage 5 from the predetermined position, the cleaner A is positionedand guided by both the left edge 4b of the original setting board 4 andthe left edge 2a of the slit 2 of the casing member 1, and the chargercleaning front end portion A' of the cleaner A is inserted while forcingdown the tongue 7c of the outer flexible sheet 7 bonded to the reflector6 and causing the inner flexible sheet 8 to hang down to downstand untilthe charger cleaning front end portion A' comes in contact with thecharge wire 10b of the main charger 10.

In this condition if an attempt is made to shift the cleaner A in thedirection of arrow C in FIG. 8 longitudinally along the slit 2 of thecasing member 1, the cleaner A abuts the inclined edge 7b of the outerflexible sheet 7, and if the cleaner A is further moved laterally in thedirection of C, the longitudinal sheet edge 7a of the flexible sheet 7is caused to be partially raised. Therefore, as shown in FIGS. 2 and 8,the outer flexible sheet 7 fixed to the reflector 6 is partially raised,while the inner flexible sheet 8 partially hangs down. Thus, bylaterally moving the cleaner A while being guided by both the left edge4b of the original setting board 4 and the left edge 2a of the slit 2,it is possible to clean the charge wire 10b of the main charger 10 bythe cleaner A while temporarily opening the cleaner insertion passage 5open.

By carrying out such cleaning operation through reciprocating lateralmovement of the cleaner A three cycles or so, the charge wire 10b can besufficiently cleaned.

To withdraw the cleaner A from the cleaner insertion passage 5, thecleaner A is reset to its original predetermined position and thenpulled off. After the cleaner A is removed from the cleaner insertionpassage 5, the flexible sheets 7, 8 are restored to their original flatsheet configuration by their own resiliency, and therefore, as shown inFIG. 1, the cleaner insertion passage 5 is completely shut off by thetwo flexible sheets 7, 8. In such a shut off condition of the cleanerinsertion passage 5, there is no possibility of entry onto thephotoreceptor drum 11 of stray light from an external source or from theexposure lamp 3 through the opening 6a of the reflector 6 formed on thecleaner insertion passage 5, nor is there possibility of leakage oflight illuminated from the exposure lamp 3 through the flexible sheets7, 8.

In the above described embodiment, the charger cleaning front endportion A' of the cleaner A as shown in FIG. 9 is inserted through theopen gap 5a defined between the left edge 4b of the original settingboard 4 and the left edge 2a of the slit 2 to clean the charge wire 10bof the main charger 10; but it is also possible to clean the exposurelamp 3, for example, by using the same cleaner A.

In this case, if an exposure lamp cleaning front end portion A" of thecleaner A as shown in FIG. 9 is inserted through the open gap 5a, abrush portion formed at the exposure lamp cleaning front end portion A"comes into slidable contact with the outer periphery of the exposurelamp 3. Thus, by laterally moving the cleaner A in the same way asdescribed above, it is possible to clean the exposure lamp 3. In thelateral movement of the cleaner A in this case as well, both the leftedge 4b of the original setting board 4 and the left edge 2a of the slit2 function as a guide for the cleaner A when it is moved.

Interior components to be cleaned by the cleaner A through theutilization of the open gap 5a between the left edge 4b of the originalsetting board 4 and the left edge 2a of the slit 2 are not limited tothe charge wire 10b of the main charger 10, but they may be, forexample, the exposure lamp 3 and/or any other interior components.

Secondly, another embodiment of the invention will be described withreference to FIGS. 10 and 11. It is noted that components having thesame functions as those in the foregoing embodiment are indicated by thesame reference numerals or characters and the description of thosecomponents are omitted hereinafter.

A reflector 6 has an outer side flexible sheet 7 bonded thereto in sucha way as to cover an opening 6a of the reflector 6 formed on a cleanerinsertion passage 5. The flexible sheet 7 has light reflectingproperties and is so constructed as to concurrently serve as a part ofthe reflector 6. The mounting arrangement of the flexible sheet 7relative to the reflector 6 is the same as that described in theembodiment 1, and concretely it is as shown in FIG. 1.

An inner flexible sheet 8 disposed opposite to the flexible sheet 7shown in FIG. 10, mounted in such a way with as predetermined space inbetween as to cover an opening 10c of a main charger case 10a for a maincharger 10 from inside. This flexible sheet 8 has both light shieldingproperties and electroconductive properties and is so constructed as toconcurrently serve as a part of the main charger case 10a. The mountingarrangement of the flexible sheet 8 is the same as that described in theembodiment 1 wherein it is mounted to the underside of the reflector 6.

Accordingly, when the front end portion of the cleaner A is insertedinto the cleaner insertion passage 5 through the open gap 5a definedbetween the casing member 1 and the original setting board 4 and ismoved in lateral directions, as shown in FIG. 11, a longitudinal sheetedge 7a of the outer flexible sheet 7 is raised at the inner side thereflector 6, while a longitudinal sheet edge 8a of the inner flexiblesheet 8 hangs down at the inner side of the main charger case 10a of themain charger 10. Thus, the cleaner insertion passage 5 is temporarilyopened.

According to this embodiment, the gap between the reflector 6 and themain charger 10 can be minimized, and at the same time a part of thecomponents can be replaced by lightweight flexible sheets 7, 8. Thus, itis possible to further facilitate size reduction. weight reduction, andreduction of the production cost.

In the above described embodiment, the cleaner insertion passage 5 islocated within a space extending from the open gap 5a defined betweenthe casing member 1 and the original setting board 4 to the charge wire10b of the main charge 10 via the reflector 6; but the location of thecleaner insertion passage 5 is not limited to that described in thisembodiment. That is, it can be arranged that flexible sheets 7, 8 havinglight shielding properties which can shut off the cleaner insertionpassage 5 are disposed between the wall portions of the components whichmay interfere with cleaning operation when the cleaner A is inserted forcleaning members or other wall portions. so as to permit cleaningoperation while the flexible sheets 7, 8 are temporarily held open onlywhen the cleaner A is inserted to clean the components. Through thisarrangement, the possibility of entry of stray light and the like ontothe photoreceptor drum 11, which may be involved in the formation ofsuch cleaner insertion passage 5, can be eliminated, and furthermore itis possible to perform effective cleaning of the desired components onlyby inserting the cleaner A from outside into the cleaner insertionpassage 5 and moving the cleaner laterally.

In the above embodiment, two flexible sheets 7, 8 having light shieldingproperties are individually disposed at the outer side and at the innerside on the cleaner insertion passage 5 in the machine, in such a waythat the flexible sheets 7 and 8 are opposite to each other, with apredetermined spacing in between, so that the cleaner insertion passage5 is shut off; but when light shielding effect on the cleaner insertionpassage 5 can be sufficiently obtained, only one flexible sheet may beprovided instead of two. However, in order to ensure sufficient lightshielding effect on the cleaner insertion passage 5, it is preferablethat at least two flexible sheets 7, 8 are provided on the cleanerinsertion passage 5. By virtue of such an arrangement, it is possible topositively avoid the possibilities of leakage of light from the exposurelamp 3 through the flexible sheets 7, 8 and/or entry of stray light andthe like onto the photoreceptor drum 11 through the opening 6a of thereflector 6 formed on the cleaner insertion passage 5. It is to beunderstood that all these arrangements are included in the subjectmatter of the present invention.

As described above, the copying machine of the invention is: a copyingmachine having a casing member forming a top wall of the machine, thecasing member being formed with a slit for directing the light from anexposure lamp toward an original setting board, the exposure lamp beingdisposed under the casing member, the original setting board beingmovable on the casing member for reciprocation in the right and leftdirections, characterized in that the copying-purpose movable range ofthe original setting board is defined so that the slit is covered by theoriginal setting board irrespective of the position of the originalsetting board during its reciprocating movement on the casing member forcopying operation, and in that the original setting board is movablebeyond its copying-purpose movable range and at least in one direction,either rightward or leftward, when it is not in copying operation, thelimit for the movement in one direction of the original setting boardbeing set so that an open gap is defined between an edge of the originalsetting board and an edge of the slit to provide a passage for cleanerinsertion which leads to the interior of the machine, when the originalsetting board is moved to the limit beyond the moving movable range. Theedge of the original setting board and the edge of the slit are soformed as to serve as a guide for the cleaner during cleaner operation.

Through this arrangement, dust and the like can be prevented fromentering into the interior of the machine through the slit of the casingmember during copying operation or the like. In addition, when interiorcomponents are to be cleaned, the cleaner is inserted from outsidethrough the open gap of the cleaner insertion passage and the interiorcomponents can be cleaned by simply externally operating the cleaner. Inthis way, the arrangement permits direct cleaning of the interiorcomponents through external control, and therefore, the number ofcomponents can be considerably decreased, making it possible to achievesize reduction, weight reduction, and reduction of the production cost.In addition, smooth cleaning performance and improved cleaningefficiency can be assured.

In the copying machine of the invention, there is provided, on thecleaner insertion passage accessible from outside the machine, aflexible sheet having light shielding properties in such a way as toshut off the passage. With this arrangement, it is possible to clean theinterior components simply by inserting the cleaner from outside intothe cleaner insertion passage and externally operating the cleaner,which naturally results in considerable improvement in cleaner operationand cleaning efficiently. In addition, the arrangement prevents straylight et cetera from an external light source or the exposure lamp fromfalling onto the photoreceptor drum within the machine through thecleaner insertion passage, thereby permitting to maintain excellentcopying performance. In addition, the arrangement permits sizereduction, weight reduction, and reduction of the production cost.

In the copying machine of the invention, flexible sheets areindividually disposed at the outer side and at the inner side on thecleaner insertion passage leading to the interior of the machine in sucha way as to shut off the passage, and are opposite to each other with apredetermined spacing in between. With this arrangement, in addition tothe above mentioned advantages, it is possible to positively eliminateleakage of light from the exposure lamp passing through the flexiblesheets, and stray light and the like from an external light source etcetera onto the photoreceptor drum.

Also, in the copying machine of the invention, the flexible sheetdisposed at the outer side has light reflecting properties so that itconcurrently serves as a part of a reflector. The flexible sheetdisposed at the inner side has electroconductive properties so that itconcurrently serves as a part of a main charger case. Through thisarrangement, in addition to the above described advantages it ispossible to obtain increased flexibility of design with respect tocopying machines, and also to minimize the gap between the reflector andthe main charger, to thereby further facilitate size reduction, weightreduction, and reduction of the production cost.

Furthermore, in the copying machine of the present invention, theflexible sheet disposed at the outer side is formed with a inclined edgeportion along a flexible sheet portion where the cleaner is inserted soas to enable a longitudinally extending edge portion of the sheet torise outwardly of the machine as the inserted cleaner portion moves inlateral directions, while on the other hand the flexible sheet disposedat the inner side has a longitudinally extending portion adapted to hangdown inwardly of the machine as the inserted cleaner portion moves inlateral directions. Through the above described arrangement, in additionto the already described advantages, the cleaning operation of theinterior components can be smoothly performed by the cleaner withoutplastic deformation of the flexible sheets.

What is claimed is:
 1. A copying machine comprising:a photoreceptor; atop wall; a board for setting thereon an original to be copied; anexposure lamp; copying means for directing light emitted from saidexposure lamp and reflected by an original on said board onto saidphotoreceptor to form a latent image on said photoreceptor while causingsaid board to slidingly move over said top wall in a first direction;said top wall having formed therethrough a slit which is elongated in asecond direction transverse to said first direction, a passage beingformed under said top wall and a cleaner member inserted therethroughfrom said slit to a component which requires cleaning and movable insaid second direction within said passage; a main reflector disposed insaid passage, said main reflector having formed therethrough an openingwhich is elongated so as to allow said cleaner member inserted downwardthrough said passage both to pass through said opening and to be movedin said second direction; and at least one movable sub-reflectornormally positioned so as to cover said opening so as to close saidpassage and to prevent light from passing through said passage to reachsaid photoreceptor, said sub-reflector being elastic and allowing saidcleaner member to be inserted through and be moved inside said opening.2. The copying machine of claim 1 wherein said component that requirescleaning includes a charging wire extended in said second directioninside a charger case which is disposed in said passage.
 3. The copyingmachine of claim 1 wherein said at least one sub-reflector includes afirst flexible sheet and a second flexible sheet, said first and secondsheets being separated by a predetermined distance with respect to andopposite to each other and being attached on opposite sides of said mainreflector.
 4. The copying machine of claim 2 wherein said at least onesub-reflector includes a first sheet and a second sheet, said first andsecond sheets being separated by a predetermined distance with respectto and opposite to each other and being attached on opposite sides ofsaid main reflector.
 5. The copying machine of claim 3 wherein saidfirst sheet has a shielding area which serves to close said passage,said sheets each having two longitudinal edges, said first sheet havinga hook-shaped tongue-like part, said tongue-like part serving to bepushed down when said cleaner member is inserted through said passage,said longitudinal edges not being fastened to said main reflector aroundsaid main reflector opening but serving to separate from said mainreflector as said cleaner member is inserted through said tongue-likepart and moved inside said passage in said second direction and toelastically return to a sheet-like form and to close said main reflectoropening by coming to tightly contact said main reflector after saidcleaner member has passed.
 6. The copying machine of claim 4 whereinsaid first sheet has a shielding area which serves to close saidpassage, said sheets each having two longitudinal edges, said firstsheet having a hook-shaped tongue-like part, said tongue-like partserving to be pushed down when said cleaner member is inserted throughsaid passage, said longitudinal edges not being fastened to said mainreflector around said main reflector opening but serving to separatefrom said main reflector as said cleaner member is inserted through saidtongue-like part and moved inside said passage in said second directionand to elastically return to a sheet-like form and to close said mainreflector opening by coming to tightly contact said reflector after saidcleaner member has passed.
 7. The copying machine of claim 5 whereinsaid first flexible sheet has a light-reflective surface opposite saidexposure lamp.
 8. The copying machine of claim 6 wherein said firstflexible sheet has a light-reflective surface opposite said exposurelamp.
 9. The copying machine of claim 7 wherein said light-reflectivesurface of said first flexible sheet has vapor deposited aluminum. 10.The copying machine of claim 8 wherein said light-reflective surface ofsaid first flexible sheet has vapor deposited aluminum.
 11. The copyingmachine of claim 2 wherein said charger case has a charger openingcovered with a flexible, elastic, light-shielding and electroconductivesheet having two longitudinal edges, one of said two longitudinal edgesbeing firmly attached to said charger case along said charger opening,the other of said two longitudinal edges not being firmly attached tosaid charger case but being separated from said charger case along saidcharger opening by said cleaner member inserted through said passage andmoved within said passage in said second direction and to elasticallyreturn to a sheet-like form and to close said charger opening by comingto tightly contact said charger case along said charger opening aftersaid cleaner member has passed.
 12. The copying machine of claim 1,wherein the board is movable with respect to the top wall only within apredetermined range in the first direction during a copying operation ofthe copying machine, the predetermined range being such that the slit isalways covered by the board when the board is within the predeterminedrange with respect to the top wall, the board being movable beyond therange with respect to the top wall when the copying machine is not in acopying operation so as to uncover the slit, the board having an edgeextending in the second direction, the edge of the board and an edge ofthe slit serving to guide the cleaner member in a motion inside thepassage along the second direction.
 13. The copying machine of claim 12,wherein the component which requires cleaning includes a charging wireextended in the second direction inside a charger case which chargercase is disposed in the passage.